Applying precision conservation to engineering decisions

A group of faculty, staff and students worked on adapting a set of techniques called precision conservation for use in teaching and research at Bucknell. The term precision conservation refers to a set of methodologies developed by the non-profit agency Chesapeake Conservancy in an effort to more effectively prioritize environmental outreach and conservation efforts. In summer 2015, with support from an L&IT grant, Prof. Rich Crago, student Elyse Pettaway (Civil & Environmental Engineering ’17) and Bucknell GIS Specialists Janine Glathar and Luyang Ren worked with staff from Chesapeake Conservancy on a pilot project that used the three main components of Precision Conservation – (1) High Resolution Land Cover/Land Use Analysis, (2) Concentrated Flow Path Mapping, and (3)Normalized Difference Flow Index Mapping (NDFI) – to analyze a small section of the Buffalo Creek Watershed. The methodologies are designed to improve the accuracy and resolution of land cover classification data, and provide a more nuanced model of how water flows across land and where it accumulates. Incorporating these methodologies improves our ability to predict nutrient and sediment load that results from runoff, and can lead to more informed decisions on site selection and design for environmental remediation projects.

Elyse Pettaway’s work was funded through a PUR summer research grant and was instrumental in helping adapt Chesapeake Conservancy’s methods for our research and teaching purposes at Bucknell. Prof. Crago’s work was funded through a Mellon Course Integration grant and led to a re-imagining of his CENG421 (Civil & Environmental Engineering – Hydrology) course. Over the course of the summer and early fall of 2015, Prof. Crago worked with local landowners and conservation organizations to create a service learning project that would give students an opportunity to work with a local landowner on designing an engineering solution that would improve the quality of runoff across that landowner’s property.

In the lab, students worked with GIS software to analyze land-cover classification and elevation data and calculate stormwater flow paths. Then, spreading out among the fields they had studied in the lab, the students checked their predictions against what was actually happening on the ground. Back in the lab, they used that data to find areas where water-protection projects would have the most impact, then devised solutions, including retention ponds, engineered swales (shallow, vegetated ditches) and vegetated streambank buffers.

Prof. Crago’s CENG 421 has been taught three times now, and he continues to work with research students on precision conservation methods.